MIPS: add RTC support for loongson1B

Add RTC support(TOY counter0) for loongson1B SOC

Signed-off-by: zhao zhang <zhzhl555@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 221 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 3a125b835546..850febcbaf73 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1070,4 +1070,14 @@ config RTC_DRV_PUV3
           This drive can also be built as a module. If so, the module
           will be called rtc-puv3.
 
+config RTC_DRV_LOONGSON1
+        tristate "loongson1 RTC support"
+        depends on MACH_LOONGSON1
+        help
+          This is a driver for the loongson1 on-chip Counter0 (Time-Of-Year
+          counter) to be used as a RTC.
+
+          This driver can also be built as a module. If so, the module
+          will be called rtc-ls1x.
+
 endif # RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 6e6982335c10..6c9387a3a3ad 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_RTC_DRV_ISL1208)	+= rtc-isl1208.o
 obj-$(CONFIG_RTC_DRV_ISL12022)  += rtc-isl12022.o
 obj-$(CONFIG_RTC_DRV_JZ4740)    += rtc-jz4740.o
 obj-$(CONFIG_RTC_DRV_LPC32XX)   += rtc-lpc32xx.o
+obj-$(CONFIG_RTC_DRV_LOONGSON1) += rtc-ls1x.o
 obj-$(CONFIG_RTC_DRV_M41T80)    += rtc-m41t80.o
 obj-$(CONFIG_RTC_DRV_M41T93)    += rtc-m41t93.o
 obj-$(CONFIG_RTC_DRV_M41T94)    += rtc-m41t94.o
diff --git a/drivers/rtc/rtc-ls1x.c b/drivers/rtc/rtc-ls1x.c
new file mode 100644
index 000000000000..07e81c5f8247
--- /dev/null
+++ b/drivers/rtc/rtc-ls1x.c
@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2011 Zhao Zhang <zhzhl555@gmail.com>
+ *
+ * Derived from driver/rtc/rtc-au1xxx.c
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/rtc.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/types.h>
+#include <linux/io.h>
+#include <asm/mach-loongson1/loongson1.h>
+
+#define LS1X_RTC_REG_OFFSET     (LS1X_RTC_BASE + 0x20)
+#define LS1X_RTC_REGS(x) \
+                ((void __iomem *)KSEG1ADDR(LS1X_RTC_REG_OFFSET + (x)))
+
+/*RTC programmable counters 0 and 1*/
+#define SYS_COUNTER_CNTRL               (LS1X_RTC_REGS(0x20))
+#define SYS_CNTRL_ERS                   (1 << 23)
+#define SYS_CNTRL_RTS                   (1 << 20)
+#define SYS_CNTRL_RM2                   (1 << 19)
+#define SYS_CNTRL_RM1                   (1 << 18)
+#define SYS_CNTRL_RM0                   (1 << 17)
+#define SYS_CNTRL_RS                    (1 << 16)
+#define SYS_CNTRL_BP                    (1 << 14)
+#define SYS_CNTRL_REN                   (1 << 13)
+#define SYS_CNTRL_BRT                   (1 << 12)
+#define SYS_CNTRL_TEN                   (1 << 11)
+#define SYS_CNTRL_BTT                   (1 << 10)
+#define SYS_CNTRL_E0                    (1 << 8)
+#define SYS_CNTRL_ETS                   (1 << 7)
+#define SYS_CNTRL_32S                   (1 << 5)
+#define SYS_CNTRL_TTS                   (1 << 4)
+#define SYS_CNTRL_TM2                   (1 << 3)
+#define SYS_CNTRL_TM1                   (1 << 2)
+#define SYS_CNTRL_TM0                   (1 << 1)
+#define SYS_CNTRL_TS                    (1 << 0)
+
+/* Programmable Counter 0 Registers */
+#define SYS_TOYTRIM             (LS1X_RTC_REGS(0))
+#define SYS_TOYWRITE0           (LS1X_RTC_REGS(4))
+#define SYS_TOYWRITE1           (LS1X_RTC_REGS(8))
+#define SYS_TOYREAD0            (LS1X_RTC_REGS(0xC))
+#define SYS_TOYREAD1            (LS1X_RTC_REGS(0x10))
+#define SYS_TOYMATCH0           (LS1X_RTC_REGS(0x14))
+#define SYS_TOYMATCH1           (LS1X_RTC_REGS(0x18))
+#define SYS_TOYMATCH2           (LS1X_RTC_REGS(0x1C))
+
+/* Programmable Counter 1 Registers */
+#define SYS_RTCTRIM             (LS1X_RTC_REGS(0x40))
+#define SYS_RTCWRITE0           (LS1X_RTC_REGS(0x44))
+#define SYS_RTCREAD0            (LS1X_RTC_REGS(0x48))
+#define SYS_RTCMATCH0           (LS1X_RTC_REGS(0x4C))
+#define SYS_RTCMATCH1           (LS1X_RTC_REGS(0x50))
+#define SYS_RTCMATCH2           (LS1X_RTC_REGS(0x54))
+
+#define LS1X_SEC_OFFSET         (4)
+#define LS1X_MIN_OFFSET         (10)
+#define LS1X_HOUR_OFFSET        (16)
+#define LS1X_DAY_OFFSET         (21)
+#define LS1X_MONTH_OFFSET       (26)
+
+
+#define LS1X_SEC_MASK           (0x3f)
+#define LS1X_MIN_MASK           (0x3f)
+#define LS1X_HOUR_MASK          (0x1f)
+#define LS1X_DAY_MASK           (0x1f)
+#define LS1X_MONTH_MASK         (0x3f)
+#define LS1X_YEAR_MASK          (0xffffffff)
+
+#define ls1x_get_sec(t)         (((t) >> LS1X_SEC_OFFSET) & LS1X_SEC_MASK)
+#define ls1x_get_min(t)         (((t) >> LS1X_MIN_OFFSET) & LS1X_MIN_MASK)
+#define ls1x_get_hour(t)        (((t) >> LS1X_HOUR_OFFSET) & LS1X_HOUR_MASK)
+#define ls1x_get_day(t)         (((t) >> LS1X_DAY_OFFSET) & LS1X_DAY_MASK)
+#define ls1x_get_month(t)       (((t) >> LS1X_MONTH_OFFSET) & LS1X_MONTH_MASK)
+
+#define RTC_CNTR_OK (SYS_CNTRL_E0 | SYS_CNTRL_32S)
+
+static int ls1x_rtc_read_time(struct device *dev, struct rtc_time *rtm)
+{
+        unsigned long v, t;
+
+        v = readl(SYS_TOYREAD0);
+        t = readl(SYS_TOYREAD1);
+
+        memset(rtm, 0, sizeof(struct rtc_time));
+        t  = mktime((t & LS1X_YEAR_MASK), ls1x_get_month(v),
+                        ls1x_get_day(v), ls1x_get_hour(v),
+                        ls1x_get_min(v), ls1x_get_sec(v));
+        rtc_time_to_tm(t, rtm);
+
+        return rtc_valid_tm(rtm);
+}
+
+static int ls1x_rtc_set_time(struct device *dev, struct  rtc_time *rtm)
+{
+        unsigned long v, t, c;
+        int ret = -ETIMEDOUT;
+
+        v = ((rtm->tm_mon + 1)  << LS1X_MONTH_OFFSET)
+                | (rtm->tm_mday << LS1X_DAY_OFFSET)
+                | (rtm->tm_hour << LS1X_HOUR_OFFSET)
+                | (rtm->tm_min  << LS1X_MIN_OFFSET)
+                | (rtm->tm_sec  << LS1X_SEC_OFFSET);
+
+        writel(v, SYS_TOYWRITE0);
+        c = 0x10000;
+        /* add timeout check counter, for more safe */
+        while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TS) && --c)
+                usleep_range(1000, 3000);
+
+        if (!c) {
+                dev_err(dev, "set time timeout!\n");
+                goto err;
+        }
+
+        t = rtm->tm_year + 1900;
+        writel(t, SYS_TOYWRITE1);
+        c = 0x10000;
+        while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TS) && --c)
+                usleep_range(1000, 3000);
+
+        if (!c) {
+                dev_err(dev, "set time timeout!\n");
+                goto err;
+        }
+        return 0;
+err:
+        return ret;
+}
+
+static struct rtc_class_ops  ls1x_rtc_ops = {
+        .read_time      = ls1x_rtc_read_time,
+        .set_time       = ls1x_rtc_set_time,
+};
+
+static int __devinit ls1x_rtc_probe(struct platform_device *pdev)
+{
+        struct rtc_device *rtcdev;
+        unsigned long v;
+        int ret;
+
+        v = readl(SYS_COUNTER_CNTRL);
+        if (!(v & RTC_CNTR_OK)) {
+                dev_err(&pdev->dev, "rtc counters not working\n");
+                ret = -ENODEV;
+                goto err;
+        }
+        ret = -ETIMEDOUT;
+        /* set to 1 HZ if needed */
+        if (readl(SYS_TOYTRIM) != 32767) {
+                v = 0x100000;
+                while ((readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TTS) && --v)
+                        usleep_range(1000, 3000);
+
+                if (!v) {
+                        dev_err(&pdev->dev, "time out\n");
+                        goto err;
+                }
+                writel(32767, SYS_TOYTRIM);
+        }
+        /* this loop coundn't be endless */
+        while (readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_TTS)
+                usleep_range(1000, 3000);
+
+        rtcdev = rtc_device_register("ls1x-rtc", &pdev->dev,
+                                        &ls1x_rtc_ops , THIS_MODULE);
+        if (IS_ERR(rtcdev)) {
+                ret = PTR_ERR(rtcdev);
+                goto err;
+        }
+
+        platform_set_drvdata(pdev, rtcdev);
+        return 0;
+err:
+        return ret;
+}
+
+static int __devexit ls1x_rtc_remove(struct platform_device *pdev)
+{
+        struct rtc_device *rtcdev = platform_get_drvdata(pdev);
+
+        rtc_device_unregister(rtcdev);
+        platform_set_drvdata(pdev, NULL);
+
+        return 0;
+}
+
+static struct platform_driver  ls1x_rtc_driver = {
+        .driver         = {
+                .name   = "ls1x-rtc",
+                .owner  = THIS_MODULE,
+        },
+        .remove         = __devexit_p(ls1x_rtc_remove),
+        .probe          = ls1x_rtc_probe,
+};
+
+module_platform_driver(ls1x_rtc_driver);
+
+MODULE_AUTHOR("zhao zhang <zhzhl555@gmail.com>");
+MODULE_LICENSE("GPL");